ci: run tests on Python 3.10

[browniebroke]

No description provided.

[codecov]

Codecov Report

Merging #462 (0b281a2) into main (3d9851a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #462   +/-   ##
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  Coverage   99.78%   99.78%           
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  Files          27       27           
  Lines         947      947           
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  Hits          945      945           
  Misses          2        2           

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[browniebroke]

The current error:

SolverProblemError

  The current project's Python requirement (3.10.0rc2) is not compatible with some of the required packages Python requirement:
    - dataclasses requires Python >=3.6, <3.7, so it will not be satisfied for Python 3.10.0rc2
  
  Because dataclasses (0.8) requires Python >=3.6, <3.7
   and no versions of dataclasses match >=0.6.0,<0.8 || >0.8, dataclasses is forbidden.
  So, because django-codemod depends on libcst (==0.3.20) which depends on dataclasses (>=0.6.0), version solving failed.

Which seems rather strange, because dataclasses is only required by libCST for Python<3.7. This is because poetry detects 3.10 as 3.1: python-poetry/poetry#4354

It will be is fixed in Poetry 1.1.8.

[browniebroke]

On 1.1.8, I'm getting this error: python-poetry/poetry#4210

It's fixed on 1.2.0a2, but the SolverProblemError with dataclasses is not. It's backported to master, but not yet released.